Professor Robert Fluhr

Plants respond rapidly to defend themselves from multiple environmental insults that include abiotic and biotic challenges. One common manifestation of plant defense is programmed cell death (PCD). For example, when the leaves of a plant age they can die and fall off, but before doing so they 'senesce' and return their nutrients to the plant. This occurs in trees in the autumn before leaf fall. We are interested in understanding both developmental and environmental causes of PCD.

PCD is also important in plant-fungal biotrophic-type interactions where the plant host tissue is maintained by the pathogen in a ‘zombie-like’ state in service of the pathogen. However in a resistance response, the infected parts of the plant can elect to undergo a local process of PCD, isolating and trapping the disease locally. This type of PCD is called hypersensitive response and is part of an overall host defense system. However, some pathogens called necrotrophs can take advantage of this plant defense strategy and actually thrive on the dead cells that were sacrificed by the host. To achieve this, the pathogen secretes protein effectors or toxins that result in host cellular mismanagement. We wish to understand molecular aspects of plant-pathogen interactions by defining the spatial and temporal context of plant responses and how pathogens and the environment evoke such responses.